Process for breaking petroleum emulsions



rapid process for separating emulsion which atentedl July ill 2,324,489 PROCESS FUR BREAKING PETROLEUM EMULSIONS it ti Melvin De Groote, University City, and Bernhard Keiser, Webster Groves, Mo., assignors to Petrolite Corporation, Ltd., Wilmington, Del., a corporation of Delaware No Drawing. Application July 7, 1941, Serial No. 401,377

M Claims. ((31. 252-341) This invention relates primarily to the resoluderived by esterification of one mole of a glycol tion of petroleum emulsions. of the kind above described, with two moles of a One object of our invention is to provide a novel fractional ester of the kind previously described. process for resolving petroleum emulsions of the The formation of the compound may be indicated water-in-oil type, that are commonly referred to by the following reaction, although obviously, it as cut oil, roily oil, emulsified oil, etc., and is immaterial what particular procedure is emwhich comprise fin droplets of naturally-occurployed to produce the particular chemical comring waters or brines dispersed in a more or less pound or product: permanent state throughout the oil which constitutes the continuous phase of the emulsion. T D COO Another Object is to provide an eclJnomical and r D rn-J-CZII4 D have been prepared under controlled conditions AS indicated P v ous y. the Polybasic acids e from mineral oil, such as crud petroleum and p y a l it d t e p having t r relatively. soft waters or weak brines. Conn x C b atoms, for Example, oxalic, trolled emulsification and subsequent demulsifi- Ionic, 8110011116, ta ic, and adip c- Sim y, cation under the conditions just mentioned is of one ay p y acids h s fumaric, maleic. significant valu i removin riti artj glutaconic, and various Others, including citric, ularly inorganic salts, from pipeline oil. malic, tartaric, and the like. The selection of the The new chemical compound or composition of particular trlbasic or dibasic acid employed is matter herein described, and intended to be used u l y on ern d lar y w h v i e f as the demulsifier of our process, is exemplified manufacture of the finished ester, and also of by the acidic, or preferably, neutral ester, dethe p ice of the reactants- Generally peaking, rived by complete esterification of one mole of a the high r t temperature employed, the easier poly'alkylene glycol of the kind hereinafter de-' t is to obta l e yields f e esterified p scribed, with two moles of a fractional ester de- Although oxalic acid is comparatively rived from a hydroxylated material of the kind c ap, it c p s S t readily at Slightly herein described, and a polybasic carboxy acid above the boiling Point Of Waters having not over six carbon atoms, son, it is more desirable to use an acid which is If a hydroxylated material, indicated for the m r resistant to py ly imil rly, when a sake of convenienc by th form lt TQOH, i r polybasic acid is available in the form of an anacted with a polybasic carboxy acid, which, simiy r d u h y de s apt to p d e t e larly, may conveniently be of the dibasic type and ester with greater case than the acid itself. For indicated by the formula HOOC.D.COOH, then this as n, ma anhydride is parti u arly the fractional ester obtained by reaction be- 5 d p and so, everything e se co tween equimolar quantities may be indicated by th s i p ively low on aper molar b i the following formula: even though somewhat higher on a per pound basis. Succinic acid or the anhydride has many of the attractive qualities of maleic anhydride;

The poly h l e y l m y be characterized y 40 and this is also true of adipic acid. For purposes materials of the kind Such as h ptaethylene gly of brevity, the bulk of the compounds, hereinafter col, octaethylene glycol, nonaethylene glycol, illustrated will refer to the use of maleic anhydecaethylene glycol, to and including heptadecadride, although it is understood that any other ethylene glycol. For convenience these polysuitable polybasic acid may be employed. Furethylene glycols may be indicated by the followthermore, for purposes of convenience, reference ing formula: I is made to the use of polyethylene glycols. As 0H(C2H4O) mH has been previously indicated, such glycol can be in which m varies from 7 through replaced by suitable polypropylene or polybutyl- Instead of polyethylene glycols, one may use compounds! polypropylene glycols or polybutylene glycols. As far as the range of oxyalkyla'ted Pompounds Thus, for convenience, in the broadest aspect, the employed as reactants is concei'nei it 15 5 pref polyalkylene glycols employed may be indicated erence to employ those havmg approximately by the following formula: I 8-12 oxyalkylene groups, particularly 8-12 oxyethylene groups. The preference to use the oxyethylated compounds is due, largely, to the fact in which m has its previous significance, and n that y are commercially available, d p represents a numeral varying from 2 to 4. ticularly so in two desirable forms. The most Thus, the bulk of the materials herein contemdesirable form is the so-called nonaethylene plated .may be indicated within certain variaglycol, which, although consisting largely of nontions, as hereinafter stated, by the neutral ester 6 aethylene glycol, may contain small amounts of heptaethylene and octaethylene glycols, and possibly minor percentages of the higher homologs. Such glycols represent the upper range of distillable glycols; and they may be convenientlyreferred to as upper distillable ethylene glycols. There is no particularly good procedure for making a sharper separation on a commercial scale; and it is understood that mixtures of one or more of the glyco1s may be employed, as well as a single glycol. As pointed out, it is particularly preferred to employ nonaethylene glycol as commercially available, although it is understood that this product contains other homologs, as indicated.

Substantially as desirable as the upper distillable pfilyethylene glycols, are the lower nondistillable polyethylene glycols. are available in the form of a waxy water-soluble material, and the general range may vary somewhat from decato tetradeca-ethylene glycol. As is well understood, the method of producing such glycols would cause some higher homologs to be formed; and thus, even in this instance, there may be present some ox'yethylene glycols within the higher range above indicated. One

, need not point out that these particular compounds consist of mixtures, and that in some instances, particularly desirable esters are obtained by making mixtures of the liquid nonaethylene glycol with the soft, waxy, lower non-distillable polyethylene glycols. For the sake of convenience, reference in the examples will be to nonaethylene glycol; and calculations will ,be based on a theoretical molecular weight of 414.

Actually, in manufacture the molecular weight' of the glycol employed, whether a higher dis.- tillable polyethylene glycol or a lower non-distillable polyethylene glycol, or a mixture of the same. shoud be determined and reaction conducted on the basis of such determination, particularly in conjunction with the hydroxyl or acetyl value.

It has been previously pointed out that it is immaterial how the compounds herein contemplated are manufactured, although we have found it most desirable to react the selected glycol, or mixtures of glycols, with maleic anhydride in a ratio of two moles of the anhydride for one mole of the glycol. Under such circumstances, we have found little tendency to form longer chain polymers; and in fact, the product of reaction, if conducted at reasonably low temperatures, appears to be largely monomeric. For convenience, such intermediate product may then be considered as a dibasic or polybasic acid. One mole of the intermediate so obtained is then reacted with two moles of the alcoholic material of the kind subsequently described.

It is to be noted, however, that if one prepares a fractional acidic ester, then if two moles of the fractional acidic ester are reacted with one mole of the polyethylene glycol, there is no possibility for the formation of polymeric types of esterification products under ordinary conditions.

The alcoholic bodies employed as reactants in one mode of manufacture of the present compounds are hydroxylated acylated monoamino bodies free from ether linkages, and of the following formula type:

in which R.COO represents the o y-acyl radical derived from a monobasic detergent-forming These materials acid; T represents a. hydrogen atom or a nonhydroxy hydrocarbon radical, or the acylated radical obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by' the acyl radical of a monobasic carboxy acid having less than eight carbon atoms; n represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; m represents the numeral 0, 1, or 2; and m" represents the numeral 0, 1, or 2, with the proviso that m-l-m'+m"=3.

One can obtain or manufactur chemical compounds whose composition is indicated by the following formulas:

If, in the above formulas, T represents an amino hydrogen atom. as well as a substituent therefor, then the formulas above described may be summarized by the following formula:

However, the radical C2H4, which appears in the above formula, may represent any similar radical, such as a CaHa radical, a CQHB radical, etc., and therefore, the above formula may be indicated as follows:

in which H.000 represents the oxy-acyl radica derived from a monobasic detergent-forming acid; T represents a hydrogen atom or a nonhydroxy hydrocarbon radical, or the acylated radical obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; n represents a small whole number, which is less than 10; m represents the numeral 1, 2, or 3; 111," represent the numeral 0, 1, or 2; and m" represents the numeral 0, 1, or 2, with the proviso that m +ml n 3 a In the above formulas it has been pointed out that T represents a hydrogen atom, or a nonhydroxy aliphatic hydrocarbon radical, such as a methyl radical, ethyl radical, propyl radical, amyl radical, octadecyl radical, etc. However, T may also represent a non-hydroxy alicyclic radical, such as a cyclohexyl radical or a non-hydroxy aralkyl radical, such as a benzyl radical; or T may represent the acylated radical obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical, or the equivalent thereof, by the acyl radical of a monobasic carboxy acid, such as acetic acid, butyric acid, heptoic acid, or the like; all of which are characterized by having less than eight carbon atoms. The alkylol radical prior, to acylation, may be a hydroxy alicyclic or a hydroxy aralkyl radical, provided the hydroxy radical is attached to the aliphatic residue of the ara kyl adical.

- sent any monobasic detergent-forming carboxy acid, such as a typical fatty acid or abietic acid or naphthenic acid.

Typical fatty acids are those which occur in naturally-occurring oils and fats, and generally have eight or more carbon atoms and not over 32 carbon atoms. Common examples include oleic acid, stearic acid, linoleic acid, linolenic acid, ricinoleic acid, erucic acid, palmitic acid, myristic acid, etc. These acidscombine with alkali to produce soap or soap-like materials, and-are commonly referred to as being monobasic detergentforming carboxy acids.

The alkylol radical, previously referred to, prior to esterification, may be a hydroxy alicyclic or a hydroxy aralkvl radical, provided the hydroxy radical is attached to the aliphatic residue of the aralkyl radical.

As to the amines above described, which happen to be tertiary amines, it may be Well to point out that these may be formed readily by a reaction involving an ester of the selected detergent-forming acid, for instance, a fatty acid ester, such as the glyceride, and a corresponding amine. This may be illustrated inthe following manner:

' 0H.C:H4

OH.C2HFN R.COOC3H5 ncoo R.COO-C3H5 R.COO

R.COO

R.COOC3H5 R.COO

R.COO

R.COOCaHb R.COO

R.CO0.C;H4

If triethanolamine, employed in the above formula, is replaced by ethyl diethanolamine, then one would obtain one of the remaining types of tertiary amines illustrated. Reference is made to Patent No. 2,167,349, dated July 25, 1939, to De Groote, Keiser and Blair.

In the remaining type of material there is an amino hydrogen atom present. The manufacture of such material may be illustrated by the following reactions:

However, if maximum yields are not necessary,

one need-not resort to reactions of the kind previously described to produce secondary amines, but one may employ the following type of reaction:

OH.C2H4

R.COO OH.C2H4

acoo-mm NH ancooclm 011mm OH.C2H4

NH orLcani H.000 OH.C:H4NH:

R.C00C;Ht olrcfimNm 3RCOO.CgH NH C:H5(0H)a 12.000 olzwlmNrn Suitable primary and secondary amines, which may be employed to produce materials of the kind above described, include the following: diethanolamine, monoethanolamine, ethyl ethanolamine, methyl ethanolamine, propanolamine, dipropanolamine, propyl propanolamine, etc. Other examples include cyclohexylolamine, dicyclohexylolamine, cyclohexyl ethanolamine, cyclohexyl propanolamine, benzylethanolamine, benzylpropanolamine, pentanolamine, hexanolamine, octylethanolamine, octadecylethanolamine, cyclohexanolethanolamine, etc.

Similarly, suitable tertiary amines which may be employed include the following: triethanolamine, diethanolalkylamines, such as diethanol ethylamine, diethanol propylamine, etc. Other examples include diethanol methylamine, tripropanolamine, dipropanol methylamine, cyclohexanol diethanolamine, dicyclohexanol ethanolamine, cyclohexyl diethanolamine, dicyclohexyl ethanolamine, dicyclohexanol ethylamine, benzyl diethanolbenzyl dipropanolamine, tripentanolamine, trihexanolamine, hexyl ethanolamine, octadecyl diethanolamine, etc.

Reference is again made to the formula which summarizes the various hydroxylated amines used as intermediate raw materials, viz.:*

in which the characteristics have their previous significance. Attention is directed to the fact that where the substituted alkyl radical OH.R.COO.CH-

appears, a suitable non-aryl radical other than an aliphatic residue may serve as the functional equivalent; for instance, an alicyclic radical derived from a cyclohexyl radical, or an aralkyl radical derived from a benzyl radical. In other words, in the hereto appended claims references to the CnH,2n radical; as such, or as an alkyl radical or residue, is intended in the broad sense to include the alicyclic radical or residues, or the aralkyl radicals or residues which are the equivalent thereof. There is no intention to include an aromatic radical where there is a direct linkage between the aromatic nucleus and the amino nitrogen atom, for the reason that such products have little or no basicity and do not have the characteristic properties of the amines previously described. I

In indicating the various hydroxylated tertiary amines of the non-aryl type, which may be employed to produce the amine contemplated as the demulsifying agent of the present process, it is desirable to indicate that amines of the type where a hydroxy acyl radical replaces a hydrogen atom of the hydroxyl radical of the hydroxy tertiary amine, are not included within the broad class of hydroxy tertiary amines, unless there is another hydroxyl radical attached to the usual alkyl radical. For instance, if ethyl diethanolamine is treated with two moles of lactic acid so as to form the dilactyl compound of the following formula:

v on

CHsHC-OC:H4

on o CHaH-OC;HN

I Cant" then it is understood that such materials would not represent a hydroxy tertiary amine within the meaning or scope, as herein employed. If, on the other hand, triethanolamine were treated with lactic acid, so as to give monolactyl triethanolamine of the following composition:

on o

CH3CHC-O-C1H4 onolnl-N OHCIHL then such compound would be included} due to the presence of one or more hydroxyl radicals attached to the alkyl radicals.

Similarly, in indicating thevarious hydroxylated primary or secondary amines of the non-aryl type, which may be employed to produce the amine contemplated as the demulsifying agent of the present process, it is desirable to indicate that amines .of the type where a hydroxy acyl radical replaces a hydrogen atom of the hydroxyl radical of a hydroxy primary or secondary amine, are not included within the broad class of hydroxy tertiary amines, unless there is another hydroxyl radical attached to the usual alkyl radical. treated with lactic acid so as to form the lactyl derivative of the following formula:

then it is understood that such materials would not represent a hydroxy primary amine within the meaning or scope, as herein employed. The same would be true if the corresponding product were derived from diethanolamine, provided both hydroxy radicals had been esterified, with lactic acid.

The manufacture of compounds from tertiary amines is relatively simple, because no precautions are necessary to prevent amidificatiom.

The selected detergent-forming acid, or ester, as, for example, a fatty oil and the selected hydroxy tertiary amine, are mixed in suitable proportions and heated at some point above the boiling point of water, for instance, C., and at a point below the decomposition point of the amine or the fatty oil, for instance, C., for a suitable period of time, such as two to eight hours. Mild agitation is employed; A catalyst, such as sodium oleate, sodium carbonate, caustic soda, etc., may be present in amounts of about one-half of 1%, or less. It is noted that the fatty acids are employed in'this instance, in the form of an ester, to wit. the glyceride, although, as previously pointed out, other functional equivalents can be readily employed with equal facility. It is to be noted that the reactions above described do not take place to any appreciable extent if the fatty acid has been converted into the soap or salt. Such salts are not,functional equivalents. As previously indicated, an ester of abietic acid or naphthenic acid might be employed, if desired.

When, however, one is employing a hydroxysecondary amine, precautions must be taken, so that one gets a substantial percentage of products derived by esterification, rather than amidification. Any suitable ester may be employed, but it is often most convenient, to employ the glyceride of a fatty acid, for instance, triricinolein. The selected glyceride and the selected hydroxy secondary amine are mixed in suitable proportions and heated at some point above the boiling point of water, for instance, 110 0., and

For instance, if ethanolamine is the salt to any marked extent; and if conducted at the lower range of reaction temperatures, there is a decided tendency to form the esterification products, rather than the amidification products.

Amide-type compounds can be converted into the ester type in themanner described in U. S. Patent No. 2,151,788, dated March 28, 1939, to Mauersberger. Similarly, amides in which there is an amino hydrogen atom attached to the amino nitrogen atom can be treated with an oxyalkylating agent such as ethylene oxide, propylene oxide, glycidol, or the like, so as to introduce a hydroxy hydrocarbon radical. In the event that no hydroxy hydrocarbon radical is available for reaction with a material such as nonaethylene glycol dihydrogen dimaleate, then, in that event the acyl radical present must contain a hydroxyl radical. In other words, one must employ ricinoleic acid, hydroxysteari-c acid, or some similar equivalent.

In order to illustrate suitable examples of the hydroxylated amines which may be used as intermediate raw materials for reaction with the polyalkylene glycol dihydrogen diacid ester, attentionis directed to the following examples:

INTERMEDIATE HYDROXYLATED AMINE Example 1 Castor oil is employed. For the sake of convenience, its molecular weight is considered as being 925. Commercial triethanolamine and castor oil in the proportion of one mole of castor oil and three moles of triethanolamine are heated to a temperature between 150-180" C. for two hours. Mild agitation is employed.

INTERMEDIATE HYDROXYLATED AMINE Example 2 The same procedure is followed as in Intermediate hydroxylated amine, Example 1, except that the ratio employed is two moles of the eastor oil to three moles of triethanolamine.

INTERMEDIATE HYDRoxYLATED AMIN'E Example 3 The same procedure is employed as in Intermediate hydroxylated amine, Example 1, except that the ratio employed is three moles of castor oil to three moles of triethanolamine.

INTERMEDIATE HYDRoxYLATED AMINE Example 4 One mole of methyl naphthenate is reacted in the manner previously described with one molecule of triethanolamine.

Methyl abietate is substituted for methyl naphthenate in Examples 4 and 5, above.

INTERMEDIATE HYDROXYLATED AMINE Example 7 Olive oil is substituted for castor oil in Examples 1 and 2, preceding, care being taken that the completed product contains at least one hydroxyethyl group.

INTERMEDIATE HYDROXYLATED AMINE Example 8 Ethyl diethanolamine is substituted for triethanolamine in Example 1, preceding.

INTERMEDIATE HYDROXYLATED AMINE Example 9 Cyclohexyl diethanolamine is substituted for ethyl diethanolamine in the example immediately preceding.

INTERMEDIATE HY RQXYLATED AMINE Example 10 Benzyl diethanolamine is substituted for ethyl diethanolamine in Example 8, above.

INTERMEDIATE HYDRoxYLATED AMINE Example 11 Castor oil (triricinolein) is employed. For

convenience its molecular weight is considered as being 925. Commercial diethanolamine and castor oil in the proportion of one mole of castor oil to three moles of diethanolamine, are heated to a temperature of -140 C., for about 12 hours. Mild agitation is employed. Loss of basicity is an indication of amidification. Time of esterification may be extended or temperature lowered or raised, so as to insure'maximum esterification, and particularly, so as to produce a product characterized by the presence of one unesterified alkylol radical attached to the amino nitrogen.

INTERMEDIATE I-IYDROXYLATED AMINE Example 12 In the previous examples where castor oil is employed, blown castor oil is substituted there- (See also U. S. Patent No. 2,225,824, dated December 24, 1940, to De Groote and Wirtel) Having obtained hydroxylated acetylated monoamino bodies or compounds free from ether linkages and of the kind previously described, the next step, of course, is to obtain fractional esters derived from nonaethylene glycol of the kind previously described in the earlier part of the present disclosure. Such materials maybe illustrated by the following examples:

GLYcoL ESTER INTERMEDIATE PRODUCT Example 1 One pound mole of nonaethylene glycol is reacted with two pound moles of maleic anhydride, so as to form nonaethylene glycol dihydrogen dimaleate.

GLYCOL ESTER INTERMEDIATE Pxonncr Example 2 A mixure of lower non-dlstil1able polyethylene glycols, representing approximately decato tetradecaethylene glycol, is substituted for nonaethylene glycol in the preceding example.

GLYCOL ESTER INTERMEDIATE Pxonu'er Example 3 GLYCOL Es'rER INTERMEDIATE PRODUCT Example 4 Adipic' acid is substituted for maleic anhydride in Examples 1-3, preceding.

GLYCOL Es'rER INTERMEDIATE Paonnc'r Example 5 Oxalic acid is substituted for maleic anhydride in Examples 1-3, preceding.

GLYCOL ESTER INTERMEEIATE Pxonnc'r Example 6 Citric acid is substituted for maleic anhydride in Examples 1-3, preceding.

GLYCOL Es'rEn INTERMEDIATE Pnonucr Example 7 Succinic anhydride is substituted for maleic anhydrlde in Examples 1-3, preceding.

The method of producing such fractional esters is well known. The general procedure is to employ a temperature above theboiling point of water and below the pyrolytic point of the reactants. The products are mixed and stirred constantly during the heating and esteriflcatlon step. If desired, an inert gas, such as dried nitrogen, or dried carbon dioxide, may be passed through the mixture. Sometimes it is desirable to add an esteriflcation catalyst, such as sulfuric acid, benzene-sulfonic acid, or the like. This is the same general procedure as employed in the manufacture of ethylene glycol dihydrogen diphthalate. See U. S. Patent No. 2,075,107, dated March 30, 1937, to Frasier.

Sometimes esteriflcation is conducted most readily in the presence of an inert solvent, that carries away the water of esterificatlon which may be formed, although, as is readily appreciated, such water of esteriflcation is absent when the reaction involves an acid anhydride, such as maleic anhydride, and a glycol. However, if water is formed, for instance, when citric acid is employed, then a solvent such as xylene may be present and employed to carry oil the water formed. The mixture of xylene-vapors and water vapors can be condensed so that the water is.

separated. The xylene is then returned to the reaction vessel for further circulation. This is a conventional and well-known procedure and requires no i'urther elaboration.

COMPOSITION or MA'rrER.Emample 1 Two pound moles of a tertiaryamine of the following composition:

R c o 0 .CZHA

OH-(hnc-N OH.CY:HA

Courosrrron or Merriam-Example 2 A comparable compound of the kind previously described is obtained from tripropanolamine instead of triethanolamine.

Comrosrrron or Manna-Example 3 Materials of the kind described in Composition of'Matter, Examples 1 and 2, are obtained from soyabean fatty acids instead of castor oil fatty acids. 1

Cdmrosrrron or Merriam-Example 4 Glycol ester intermediate products of the kind exemplified by Examples 4-7, preceding, are substituted for Glycol intermediate products, Examples l, 2 and 3 in the preceding three examples.

It is to be noted that this second step is an esterification reaction, and the same procedure is employed, as suggested above, in the preparation of the intermediate product. Needless to say, any particular method may be used to produce the desired compounds of the kind indicated. In some'instances it may be desirable to conduct the esteriflcation reaction in the presence of a non-volatile inert solvent which simply acts as a diluent or viscosity reducer.

, In the preceding examples, attention has been directed primarily to the monomeric form, or at least, to the form in which the bifunctional alcohol, i. e., a glycol, and the polyfunctional acid, usually a bifunctional compound, react to give a chain type compound, in which the adjacent acid and glycol nucleus occur as a structural unit. For instance, in the monomeric form this may be indicated in the following manner:

acid glycol. acid If, however, one prepared an intermediate product employing the ratio of three moles of maleic anhydride and two moles of nonaethylene glycol, the tendency would be to produce a product which might be indicated in the following manner:

composition may be indicated in the following manner:

in which the characters have their previous signiflcance and a: is a relatively small whole num ber less than 10 and probably less than 5; and in the monomeric form :0, of course, is 1. The limitations on the size of a: are probably influenced largely by the fact that reaction leading to further growth is dependent upon random contact.

Some of the products are seliemulsiflable oils or seli-emulsifiable compounds; whereas, others give cloudy solutions or sols; and the most desirable type is characterized by giving a clear solution in water, and usually in the presence of soluble calcium or magnesium salts, and. frequently, in the presence of significant amounts of either acids or alkalies.

Water solubility can be enhanced in a number of ways which have been suggested by previous manufacturing directions, for instance:

(a) By using a more highly polymerized ethylene glycol;

(b) By using a polymeric form instead of a monomeric form in regard to the unit which forms the chain between the two alcoholic nuclei;

By using a polybasic carboxy acid of lower molecular weight, for instance, maleic acid, instead of adipic acid;

(d) By using an amine of a lower molecular weight or having more hydroxyl groups, as, for example, a derivative of glycerylamine.

Indeed, in many instances the hydroxylated acylated amino compound is water-soluble prior to reaction with a glycol ester. It is to be noted that in this instance, one is not limited to hydroxylated materials which are water-soluble prior to reaction with a glycol ester; but they may, in fact, be perfectly water-soluble.

Actually, a reaction involving an alcohol and an acid (esterification) may permit small amounts of either one or both of the reactants, depending upon the predetermined proportion, to remain in an unreacted state. In the actual preparation of compositions of the kind herein contemplated, any residual acidity can be removed by any suitable base, for instance, ammonia, triethanolamine, or the like, especially in dilute solution. Naturally, precaution should be taken, so that neutralization takes place without saponification or decomposition of the ester. In some cases there is no objection to the presence of the acidic group. Indeed, if a tribasic acid be employed in such a manner as to leave one free carboxyl group, then it is usually desirable to neutralize such group by means of a suitable basic material.

In the hereto appended claims, reference to a neutral product refers to one in which free carboxylic radicals are absent.

Conventional demulsifying agents employed in the treatment of oil field emulsions are used as such, or after dilution with any suitable solvent, such as water; petroleum hydrocarbons, such as gasoline, kerosene, stove oil, a coal tar product,

such as benzene, toluene, xylene, tar acid oil,

agents are sometimes used in a ratio of 1 to 10,000, or 1 to 20,000, or even 1 to 30,000, such an apparent insolubility in oil and water is not significant, because said reagents undoubtedly have solubility within the concentration employed.

other available demulsifiers, or conventional mixtures thereof. It is believed that the particular demulsifying agent or treating agent herein described will find comparatively limited application, so far as the majority of oil field emulsions are concerned; but we have found that such a demulsifying agent has commercial value, as it will economically break or resolve oil field emulsions in a number of cases which cannot be treated as easily or at so low a cost with the demulsifying agents heretofore available.

In practising our improved process for resolving petroleum emulsions of the water-in-oil type, a treating agent or demulsifying agent of the kind above described is brought into contact with or caused to act upon the emulsion to be treated, in any of the various ways, or by any of the various apparatus now generally used to resolve or break petroleum emulsions with a chemical reagent, the above procedure being used ether 'alone, or in combination with other demulsiiying procedure, such as the electrical dehydration process.

The demulsifier herein contemplated may be employed in connection with what is commonly known as down-the-hole procedure, i. e., bringing the demulsifier in contact with the fluids of cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols, such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may be employed as diluents. Miscellaneous solvents, such as pine oil, carbon tetrachloride, sulfur dioxide extract obtained in the refining of petroleum, etc., may be employed as diluents. Similarly, the material or materials herein described, may be admixed with one or more of the solvents customarily used in connection with conventional demulsifying agents, provided that such compounds are compatible. They will be compatible with the hydrophile type of solvent in all instances. Moreover, said material or materials may be used alone, or in admixture with other suitable well known classes of demulsifying agents.

It is well known that conventional demulsifying agents may be used in a water-soluble form,

or in an oil-soluble form, or in a form exhibiting both oil and Water solubility. Sometimes they may be used in a form which exhibits relatively limited oil solubility; However, since such rethe well at the bottom of the well, or at some point prior to their emergence. This particular type of application is decidedly feasible when the demulsifier'is used in connection with acidification of calcareous oil-bearing strata, especially if suspended in or dissolved in the acid'employed for acidification.

It will be apparent to those skilled in the art that residual carboxyl acidity can be eliminated by esterification with a low molal alcohol, for instance, ethyl, methyl, or propyl alcohol, by conventional procedure, so as to give a substantially neutral product. The introduction of such low molal hydrophobe groups does not seriously affect the solubility, and in some instances, gives increased resistance, to soluble calcium and magnesium salts, for such property is of particular value. Usually, however, neutralization with a dilute solution of ammonia or the like is just as practicable and less expensive.

In the hereto appended claims, it is intended that the monomeric forms contemplate also the polymeric forms, insofar that the polymeric forms are nothing more or less than a repettion of the monomeric forms several times over, with the loss of one or more moles of water.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agentcomprising a water-soluble esterification product derived by reaction between one mole of a polybasic compound, and 2 moles of a hydroxylated acylated monoamino compound free from ether linkages; the polybasic compound being the esteriflcation product of (A) a polyalkylene glycol having at least 7 and not more than 17 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms; and (B) a polybasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of more than 1 and not over 2 moles of the polybasic acid for each mole of the glycol;

- and said hydroXylated acylated amino compound free from ether linkages being of the following type:

R.coo.o,.m..),

' in which R.COO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; T represents almember of the class consisting of hydrogen atoms, non-hydroxyl hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; 11. represents a small whole number which is less than 10.; m represents the numeral 1, 2, or 3; m represents the numeral 0, '1, or 2; and 111." represents the numeral 0, 1, or 2, with the proviso that m+m+m"=3.

2. A process for breaking petroleumemulsions of the water-in-oil type, characterized-by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esterification product derived by reaction between one mole of a polybasic compound, and 2 moles of a hydroxylated acylated monoamino compound free from ether linkages; the polybasic compound being the esteriflcation productof (A) a polyalkylene glycolhaving at least 7 and not more than 1'7 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms; and (B) a polybasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of more than 1 and not over 2 moles of the polybasic acid for each mole of the glycol; and said hydroxylated acylated amino compound free from either linkages being of the following type: v

R.oo0.c..H=,.),,

' in which R.COO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; T represents a member of the class consisting of hydrogen atoms, non-hydroxy hydro--- carbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of one mole of a dibasic compound and 2 moles of a hydroxylated acylated monoamino compound free from ether linkages; the dibasic compound being the esterification product of (A) a polyalkyiene glycol having at least 7 and not more than 17 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms; and (B) a dibasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of more than 1 and not over 2'moles of the dibasic acid for each mole of the glycol; and said hydroxyiated acylated amino-ether free from ether linkages being of the following type:

in which R.C0O represents the oxy-acyl radical derived from a monobasic detergent-forming acid; '1' represents a member of the class consisting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; n represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; 111. represents the numeral 0, 1, or 2; and m" represents the numeral 0, 1, or 2, with the proviso that m+m+m"=3.

- 4. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esterification product derived by reaction between one mole of a dibasic compound and 2 moles of a hydroxylated acylated monoamino compound free from ether linkages; the dibasic compound being the esterification product of (A) a polyalkylene glycol having at least 7 and not more than 17 ether linkages; and the alkylene radical thereof containing at least 2 and not more than 4 carbon atoms; and (B) a dibasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of more than 1 "and not over 2 moles of the dibasic acid for each mole of the glycol; and said hydroxylated acylated amino-ether free from ether linkages being of the following type:

in which R.COO represents the oXy-acyl radical derived from a monobasic detergent-forming acid; T represents a member of the class consisting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; 11. represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; m represents the numeral 0, 1, or 2; and m" represents the numeral 0. 1, or 2, with the proviso that m+m'+m"=3.

5. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esteriflcation product derived by reaction between onemole of -a dibasic compound and 2 moles of a hydroxylated acylated monoamino compound free from ether linkages; the dibasic compound being the esterification product of (A) a polyethylene glycol having at least 7 and not more than 17 ether linkages; and (B) a dibasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esteriiying reactants being within the range of more than 1 and not over 2 moles of the dibasic acid for each mole of the glycol; and said hydroxylated acylated amino-ether free from ether linkages being of the following type:

aooocnmom c jm" oncnnmm' in which R.COO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; T represents a member of the class consisting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; n represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; m represents the numeral 0, 1, or 2; and m" represents the numeral 0, 1, or 2, with the proviso that m+m+m"=3.

6. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral Water-soluble chemical compound of the following type:

T'OOC.D.COO (Cal-I40) m"C2H&OOC.R.COO] 1T in which T is a radical derived by the dehydroxylation of a hydroxylated acylated amino compound free from ether linkage and of the following formula type:

acooonmom in which R.CO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; '1 represents a member of the class consisting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; n represents a small whole number which is less thanlO; m represents the numeral 1, 2, or 3; m represents the numeral 0, 1, or 2; and m" represents the numeral 0, 1, or 2, with the proviso that m+m'+m"=3; 0OC.D.COO is the acid radical derived from a dibasic acid by removal of the acidic hydrogen atoms; said acid radical having not over 6 carbon atoms; m' represents a numeral Varying from 7 to 12; and a: is a small whole number less than 10.

7. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting' the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble chemical compound of the following formula type:

in which "1" is a radical derived by the dehydroxylation of a hydroxylated acylated amino compound free from ether linkages and of the following formula type:

(ncoocnnmm (OELCnHin) m in which R.COO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; '1 represents a member of the class consisting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; n represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; m represents the numeral 0, 1, or 2; and m" represents the numeral 0, l, or 2, with the proviso that m+m'+m" -3; OOC.D.COO is the acid radical derived from a dibasic acid by removal of the acidic hydrogen atoms; said acid radical having not over 6 carbon atoms; and m' represents a numeral varying from 7 to 12.

8. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble.

chemical compound of the following formula type:

in which T is a radical derived by the dehydroxylation of a hydroxylated acylated amino compound free from ether linkages and of the following formula type:

acoocnmnm oncznmm in which R.COO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; T represents a member of the class consisting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; 11. represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; m represents the numeral 0, 1, or 2; and m" represents the numeral 0, 1, or 2, with the proviso that m+m'+m"=3; OOC.D.COO is the acid radical derived from maleic acid by removal of the acidic hydrogen atoms; and-m represents a numeral varying from '7 to 12.

9. A process for breaking petroleum emulsions of the Water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a water-soluble chemical compound of the following formula type:

in which T is a radical derived by the dehydroxylation of a hydroxylated acylated amino compound free from either linkages and of the following formula type:

in which R.COO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; T represents a member of the class consisting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical of a monobasic carboxy acid having less than 8 carbon atoms; 1:; represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; m represents the numeral 0, 1, or 2;

and m" represents the numeral 0, 1, or 2. with the proviso that m+m'+m"=3; OOC.D.COO is the acid radical derived from succinic acid by removal of the acidic hydrogen atoms; and m' represents a numeral varying from 7 to 12.

10. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble chemical compound of the following formula type:

T'OOC.D.COO(C:H4O) m'"C2HAOOC-D-COO.T'

in which T' is a radical derived by the dehydroxylation of a hydroxylated acylated amino compound free from ether linkages and of the following formula type:

in which R.COO represents the oxy-acyl radical derived from a monobasic detergent-forming acid; T represents a member of the class conslsting of hydrogen atoms, non-hydroxy hydrocarbon radicals, and acylated radicals, obtained by replacing a hydrogen atom of the hydroxyl group of an alkylol radical by the acyl radical 01' a monobasic carboxy acid having less than 8 carbon atoms; n represents a small whole number which is less than 10; m represents the numeral 1, 2, or 3; 111. represents the numeral 0, 1, or 2; and m" represents the numeral 0, 1, or 2, with the proviso that m+m'+m"=3; OOC.D.COO is the acid radical derived from adipic acid by removal of the acidic hydrogen atoms; and m' represents a numeral varying from 7 to 12.

MELVIN DE GROOTE. BERNHARD KEISER. 

